Vehicle assembly plants often produce several hundred vehicles per day. This type of production demand places a significant burden on the plant assembly operators who must construct these vehicles. Not only must the assembly operators correctly assemble various types of component configurations, but they must also meet daily production goals. To maintain a competitive position, vehicle manufacturers strive to create innovations that reduce cost while maintaining quality. One such innovation is to reduce overall vehicle assembly time.
The installation of heating, ventilation and air-conditioning (HVAC) systems into vehicles inherently poses assembly problems. Assembly problems arise with HVAC systems because the user interface mechanisms, such as knobs or switches, typically are coupled individually to the system they control. These individual coupling requirements significantly slow vehicle assembly time and increase overhead costs.
An increasingly common approach to reduce overall vehicle assembly time is to require component manufacturers to pre-assemble as much of the components as possible. The pre-assembled components are then shipped to the vehicle assembly plant for installation in a vehicle. Because the assembly operators' time is not occupied as much by pre-assembly needs, the overall amount of time spent assembling the vehicle is reduced. This reduction in time directly impacts costs by reducing overhead and increasing the rate of production.
In HVAC systems where the user interfaces are mechanical, as when knobs are used, HVAC component manufacturers couple the HVAC module to a mounting plate, such as by use of push tabs, and deliver the sub-assembly to the vehicle assembly plant. During assembly, the assembly operators have to snap fit or otherwise affix the faceplate to the mounting plate and make the connections between the function interfaces, such as rotary cylinders, and the knobs by coupling one knob individually to each function interface.
The difficulty with assembling the HVAC system in the manner described above is that once installation is complete, the assembly operators do not know if the function interfaces are properly aligned, installed and operational. The assembly operators can verify the installation only by activating the entire HVAC system. The time the assembly operators take to activate the entire HVAC system slows overall vehicle assembly time.
These disadvantages the assembly operators encounter when installing HVAC systems have made it apparent that a new technique to install the user and function interfaces is needed. This new technique should adequately couple the function interfaces to the user interfaces in one step. The new technique also should also eliminate the need for the assembly operators to verify installation by activating the entire HVAC system. The present invention is directed to meeting these ends.